1. Field of the Invention
The present invention relates to a louver assembly, and, more particularly to an improved louver assembly for an enclosure which houses HVAC equipment.
2. Description of the Prior Art
HVAC equipment may be contained in an enclosure to protect the equipment from the environment and to prevent personnel from contacting rotating, heated or other hazardous parts. When heating facilities are within the enclosure, the intake of a blower or fan applies a negative pressure to the volume or space surrounded by the enclosure to draw air into the enclosure. After a burner heats the air which is drawn in, the blower expels the air into an area to be heated through an outlet formed in the enclosure. Thus, the enclosure serves protective functions and acts as a vital part of the air transmission path.
It is disadvantageous to draw air which contains moisture or water into the enclosure, whether such moisture is in the form of rain, fog, mist or water vapor. First, the specific heat of air which contains water is higher than that of dry air. Accordingly, more energy is required, and ultimately more fuel at greater expense, to heat moist air. Second, water-laden air can damage the HVAC equipment. Over a period of time, moisture drawn into the enclosure can cause corrosion or other damage to metal and other parts of the equipment. Moreover, a sudden inflow of a large quantity of water, in the form of wind-driven rain, for example, can short-circuit electrical devices, extinguish the burner and cause belts to lose traction on their pulleys.
Devices for removing water as well as particulate matter entrained in air are known. Such devices, termed inertial separators, are well known for use in the air intakes of large turbine engines, such as those present on ships and in air craft. Inertial separators are shown in the following U.S. Pat. Nos. 4,312,645 to Mavros et al; 4,698,078 to Mavros; 3,498,205 to Kautz et al; and 3,348,466 to Lane et al. Filters used in the same environments to remove particulates are known, see U.S. Pat. No. 3,411,272 to Carmon, but filters are generally ineffective for removing water from an air stream. Rainproof louvers for enclosures are also known. See the following U.S. Pat. Nos. 4,452,024 to Sterriker et al; 4,310,993 to White; 4,064,670 to Lichtenwald; and 1,972,991 to Hinkle.
Inertial separators of the type used on ships and air craft comprise a plurality of closely spaced chevrons or V-shaped vanes held in a frame. Air flows at very high velocity through the separator. As it so flows, the air must turn or bend several times to follow the tortuous path between the vanes. Entrained particles, such as salt, sand or other particulate matter contained in air, generally have a higher mass and density than the "particles" of air in which the are entrained. As a consequence, as the entrained particles bend and turn, they are thrown outwardly against the surfaces of the vanes due to centrifugal forces thereon. Stated differently, the less massive air "particles" are capable of negotiating the bends and turns, while the particles of the more massive and more dense particulate matter are not, and these impact against the vanes. The vanes in inertial separators typically contain stops, ducts or projections which ensure that the impacted matter is not re-entrained in the high velocity air flowing therepast and conduct the impacted matter downwardly (due to gravity) to a collection area.
Inertial separators for turbine intakes are expensive to fabricate. The shapes of the vanes thereof are rather complex, and forming them is one factor contributing to the high cost. Further, the projections on the vanes represent discontinuities, adding to the complexity of the formation thereof. It is difficult, if not impossible, to form the vanes of naval and aero inertial separators by simple bending techniques.
Naval and aero inertial separators must be very efficient to protect the massive, powerful turbines and other engines thereof. This need for efficiency results in the vanes being spaced closely together. Although the close spacing increases fictional resistance to air flow, such is easily overcome by the high negative-pressure-creating power of ship-board or plane-board turbines. The close spacing, of course, contributes to the high efficiencies of the separators.
Typical rainproof louvers heretofore used contain vanes or blades which are complexly shaped and are often formed of multiple, attached pieces. Where not formed of attached pieces, the vanes or blades, in cross-section, have sinuous, multi-run configuration with varying angles between the respective runs thereof, and often include projections or protrusions which are extruded, if they do not constitute separate attached pieces.